Fountain-pen.



P. W. HOWARD. FOUNTAIN PEN. APPLICATION PI'LBD MAR. 2, 1912.

WITNESSES. INI/E/V 70/? 4; ATTORNEY Patented July 22, 1913.

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v produce the partial vacuum effectively, it is fi th rich.

FRANK W. HOWARD, OF NEVJ YORK, N. Y.

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Specification of Letters Patent.

Patented July 22., 191

Application filed March 2, 1912. Serial No. 681,121;

'To all whom it may concern:

Be it known that I, FRANK W. HOWARD, a citizen of the United States, andresident of New York cit in the countyof New York and State of Jew York,have invented certain-new and usefullmprovements in Fountain-Pens, ofwhich the following is a specification.

This invention relates to fountain pens and is particularly applicableto fountain ensof the self-filling type.

e The. barrel of the pen is provided with a moving piston or plungerwhich is advanced in the barrel when the pen is to be filled in order tocreate a partial vacuun within the.

barrel into which the ink flows. In order to necessary toprovide anefiicient packing for the plunger or piston which will preventtheleakage of air past the plunger in the workessarily comes incontactwith the ink and is subject; to the destructive actionofthe acidsa in the ink. It has been attempted to utilize leather as a material forthis packing but the leather is attacked and destroyed by the ink.

The object of this invention is to produce a packing for the plungerwhich will resist the destructive action of the ink and at the same timewhich will be soft and pliable and give an efficient air-tightaction ofthe plunger on the working stroke and permitting leakage of air past theplunger on the reverse movement or'withdrawal of the plunger.

The invention resides in the packing substance or material with which Ipack the plunger. 1n the drawing which fully illustrates my invention,Figurel is a longitudinal central section through a fountain pen of thetype referred to above, and provided with a plunger or piston having apacking of my invention. Fig. 2 is a central section through the packingor paekingwasher showing the same removed from the plunger. i

The fountain pen comprises a barrel or ink reservoir 1, having alongitudinal bore 2 in which the plunger 3 moveslongitudinally, and nearthe forwardend the bore 2 cominunicates with a chamber 4 of enlargeddiameter. The forward end of nozzle 5 of the most clearly in adjusts thevalve 13 on its seat 7.

.subjecting it to the action of at which point suitable packing 9 isprovided. The butt end of the pen is provided 1 with a threaded nipple10 upon which screws a cap 11 Whichis rigid with the stern and may beformed integral therewith as shown.

The body of the plunger 3 is of slightly taered conical foriii as shown,the reduced end of the plunger being disposed toward ,the butt end ofthe pen. The forward side of the plunger 3 receives a threaded nipple.12 which is formed on the rear end of a valve or plug 13 having aconical point 14 adapted to come upon the seat 7 The stem 8 has athreaded engagement with the rear or re duced end. of the plunger 3.

By reason of the reduced diameter of the nipple 12 an annular shoulder15 is formed on the plug or valve 13 and on this shoulder is received mypacking 16, which is in the form of a cup-shaped washer, as indicatedFig. 2. This washer has an annular conical flange 17, .and a'disk body18, with an opening 19, through which the threaded nipple 12 passes.

In the operation of the pen, the cap llis forced in suddenly so that'thepiston or plunger advances toward the forward end of the barrel,creating a partial vacuum within the barrel. As the plunger passes intothe enlarged chamber 4-, the ink flows in through the immersed end ofthe nozzle 5,"

through the duct 20, and flows around the piston or plunger into thebarrel, being forced up into the barrel by the atmospheric pressure.When the ph nger is drawn to.-

.ward the butt end of the pen, the air leaks past the .plunger. Afterthe reservoir is filled the feeding of the ink is reg ilated by screwingthe cap 11 onto nipple 10. This the pen reservoir is partially filled,the packing 1.6 is in contact with the ink and subject to thedestructive action of the ink.

A s long as In order to produce a packing which will.

resist: the action of the ink, I produce a packing washer ofsubstantially the shape shown in Fig.2, and form the same out of redvulcanized rubber of a suitable quality. As this material isrelativelyhard, it can readily be given the desired shape by cutting tools. 'Inorder to adaptthe washer for use in ink, it is then softened,preferably'by stance at a high temperature. For this pur pose, 1t 18preferable to use a vegetable oil,

an oily sub:

- pansion of the material treatment.

gradually to about 300 such as linseed oil. The heating should beaccomplished. by stages. The best results are secured by placing thewashers in cold raw linseed oil and raising l3. This raising of thetemperature should consume about a half hour. The Washers should then beleft in the oilwith the temperature maintained at 865 F. for about threeto five hours or longer, depending upon the thickness of the washers,and upon the and flexibility desired. The temperature should preferablythen be raised quite rapidly to about 400 F. and maintained at 400 forten or fifteen minutes or longer. VVashers of a thickness of 25/1000 to60/1000 of an inch will require the temperature of 365" to be maintainedfor about six hours. Vvashers having greater thickness would require alonger time. If the same bath of oil is used repeatedly, it becomesthicker and requires a longer time to accomplish the results, but isstill useful. A considerable extakes place in this \Vashers of a.thickness of wall of .053 of an inch expand to a thickness of about .065of an inch.

After treating the washers as described above, I immerse them in parathnwax at a temperature of from 212 to 300 F. for

about ten minutes immediately after taking them from the oil. This hasthe effect of preventing evaporation of the oil at the surface of theWashers and also tends to make the washers work smoothly in the barrelof the pen.

A variation may be made in the oil treatment by immersing the washers inoil at 365 F. and maintaining this temperature for two to three hours,and then rapidly raising the temperature to 480 F. for a few degree ofsoftness the temperature 5 l l l i i l l l l i stance.

moments; and then reducing thdtempelature toabout 400 to 410 F. This hasthe effect of making the finished washers tougher but seems to reducetheir durability in use.

I believe that the resisting effect of the soft rubber washer is duetothe impregna; tion of the pores of the rubber with oily sub- But it maybe an inherent property of softened vulcanized hard rubber.

If the washers are placed in oil already at a high temperature, or ifthe temperature is raised too suddenly, to a high tempera ture,the-washers will often crack or burst, or lose their shape. Suddenraising of the temperature tends to toughen the but it loses thereby inelastic qualities.

What I claim and ters Patent is:

1. A fountain pen comprising an ink reservoir, a plunger movable in saidreservoir, and a softened vulcanized porous rubber \vasher carried bysaid plunger, said Washer having its pores impregnated. with an oilysubstance, thereby producing a Washer impervious to ink and flexible.

2. A fountain pen comprising an ink reservoir, a. plunger movable insaid reservoir, and a softened vulcanized porous rubber Washer carriedby said plunger, saidwasher havingits pores impregnated with an oilysubstance and having a waxen exterior surface, and thereby producing aWasher mpervious to ink and flexible. v

Signed at New York city in the county of New York and State day of MarchA. D. 1912.

FRANK w. HOWARD.

rubber,

desire to secure by Let

